Appendicular Skeleton Flashcards
Appendicular Skeleton
- Pectoral/Pelvic Girdle
- Bones of the Limbs
Pectoral Girdle
- Consists of clavicle (anterior), scapula (posterior)
- Attach upper limb bones to axial skeleton
- Attachment points for muscles of upper limbs
- Joint structure
- > high degree of movement at glenohumeral joint
Clavicle
- Double-curved long bone
- Medial (sternal) end articulated with sternum (clavicular notch)
- Lateral (acromial) articulated with acromion of scapula
Scapula
- Triangular flat bone overlying dorsal surface of ribs 2-7
- Lateral aspect articulated with humerus and clavicle
Features
o 3 borders/ 3 angles
o Coracoid Process (arises from lateral superior border)
o Glenoid Fossa (concave articular surface – articulates with humerus)
o Spine (Lateral aspect terminated as acromion)
o Fossae (origin points for rotator cuff muscles)
Subscapular (anterior)
Infraspinous (posterior)
Supraspinous (posterior)
Proximal Humerus
- Head (articulated with glenoid fossa)
- Greater/lesser tubercles (muscle attachment)
- Intertubercular/Bicipital Sulcus (elongated groove – guides tendon of biceps brachii)
Distal Humerus
- Medial Epicondyle (O for several flexor muscles of antebrachium)
- Lateral Epicondyle (O for several extensor muscles of antebrachium)
- Capitulum (articulates with fovea of head of radius)
- Trochlea (articulates with trochlear notch of ulna)
Ulna (medial) Forearm Bone
- Trochlear Notch (C-shaped indentation – articulates with humerus)
- Olecranon Process (posterior prominence of trochlear notch)
- Coronoid Process (anterior prominence of trochlear notch)
- Radial Notch (accommodates head of radius)
Radius (Lateral) Forearm Bone
- Head (disk of proximal aspect – articulates with capitulum and radial notch)
- Radial Tuberosity (attachment for biceps brachii)
- Ulnar Notch (articulates with distal aspect of ulna)
- Styloid Process (Prominence at distal aspect – adjacent to thumb)
Carpus
- Carpal bones organised into 2 rows (proximal and distal)
- Scaphoid and Lunate (articulate with radius)
- Pisiform (sesamoid bone within tendon or flexor carpi ulnaris muscle)
Metacarpals
- 5 small bones radiating from wrist
- Proximal end (articulates with carpals)
- Distal head (articulate with bones of digits)
- Assigned Roman Numerals (lateral to medial)
Phalanges
- 14 individual bones
- Proximal, middle and distal
- Pollex has only proximal and distal
Pelvis
Composed of 4 bones
o Sacrum, Coccyx, Right and Left Ossa Coxae
Pelvic Girdle
- Right and Left Ossa Coxae only
Attaches lowers limbs to axial skeleton
o Transfer weight from upper body to lower body
o Protects visceral organs in pelvic cavity
o Each bone consists of 3 bones (ischium, ilium, pubis)
Ossa Coxae
Bones fuse between ages 13-15 o Ilium (superior aspect) o Ischium (posteroinferior region) o Pubis (anteroinferior region) o Acetabulum (articulates with head of femur) o Obturator Foramen (inferior to acetabulum – blood vessels, nerves pass)
Femur (Proximal End)
- Head (articulates with acetabulum)
- Neck (connects head to shaft)
- Greater Trochanter (projects laterally, muscle attachment)
- Lesser Trochanter (projection on posteromedial surface of neck, muscle attachment)
Femur (Shaft and Distal End)
Shaft
- Linea Aspera (vertical ridge on posterior shaft, muscle attachment point)
Distal End
- Lateral/ Medial Condyle (articulate with lateral/medial condyle of tibia)
- Intercondylar fossa (separates two condyles)
- Patellar Surface (medial depression, articulates with patella)
Patella
- Triangular sesamoid bone
- Enclosed in quadriceps tendon that secures anterior thigh muscle to tibia
- Broad superior base
- Pointed apex
- Articulates with patella surface of femur
- Protects tibiofemoral joint
Tibia (Medial) Proximal End
- Medial/Lateral Condyles (articulate with condyles of femur)
- Intercondylar Eminence (irregular projection between condyles)
- Tibial Tuberosity (attachment for patellar ligament – continuous with tendon of quadricep femoris)
Tibia (Medial) Shaft
- Anterior Border/Crest (triangular projection)
Tibia (Medial) Distal End
- Articulates with fibula and talus
- Medial Malleolus (prominent process – forms medial bulge of ankle)
Fibula (Lateral Bone)
- Does not bear weight
- Head (articulates with proximal aspect of tibia)
- Lateral Malleolus (forms lateral bulge of ankle)
Tarsus
- 7 bones (posterior half)
- Organised into two groups
- Body weight carried by talus and calcaneus
- Talus – articulates with tibia at trochlear surface and fibula at lateral aspect
- Calcaneus – forms heel of foot, provides attachment for calcaneal tendon (Achilles)
Metatarsal
- 5 small, long bones radiating from tarsus
- Distal end (articulates with phalanges)
Phalanges
- 14 individual bones
- Proximal, middle and distal
- Hallux (proximal and distal)
